cc/gapir/renderer.h

/*
 * Copyright (C) 2016 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef GAPIR_RENDERER_H
#define GAPIR_RENDERER_H

#include "gfx_api.h"

namespace gapir {

// Renderer is an interface to an off-screen rendering context. Constructing a renderer will perform
// any necessary hidden window construction and minimal event handling for the target platform.
class Renderer {
public:
    // Destroys the renderer and any associated off-screen windows.
    virtual ~Renderer() {}

    // Returns the renderer's API.
    virtual Api* api() = 0;

    template <typename T> inline T* getApi();
};

template <typename T>
inline T* Renderer::getApi() {
    if (Api* api = this->api()) {
        // Raw-pointer comparison is safe as the ID is static.
        if (api->id() == T::ID) {
            return static_cast<T*>(api);
        }
    }
    return nullptr;
}

}  // namespace gapir

#endif  // GAPIR_RENDERER_H